Reducing-mill hammer



F, R. CORNWALL. REDUCING MILL HAMMER.

APPLICATION FIL ED JULY 10,1920.

1,403,013. Patented Jan. 10,1922.

but

FREDERICK R. CORNWALL, OF ST. LOUIS, MISSOURI, ASSIGNOR TD WILLIAIMSPATENT CRUSHER ANS) PULV'JRIZER GOTLEPA'NY, OF ST. LOUIS, MISSOURI, ACORPORATION OF MISSOURI.

Specification of Letters Patent.

rammed Jan. 10, 1922.

Application filed July 10, 1920. Serial No. 385,245.

To all whom it may concern.

Be it known that I, FREDERICK R. CORN- WALL, a citizen of the UnitedStates, resid ing at St. Louis, State of Missouri, have invent-ed acertain new and useful Improvement in Reducing-Mill Hammers, of whichthe following is a full, clear, and exact description, such as willenable others skilled in the art to which it appertains to make and usethe same, reference being had to the accompanying drawings, forming partof this specification, in whichi Figure 1 represents a verticalsectional view of the housingof a mill or rotor embodying myimprovements.

Figure 2 is a sectional view taken in vertical plane parallel to thelongitudinal axis of the shaft.

Figure 3 is a detail view of one form of T-hammer.

Figure 4t is a detail view of another form of T-hammer.

Figure 5 is a diagrammatic view illustrating the relation of T-hammer tothe cage in its new or unworn condition.

Figure 6 is a view showing one of the ends of the hammer worn and afterthe same has been bent outwardly to compensate for its changing radii.

Figure 7 is a similar view showing the worn hammer reversed.

This invention relates to new and useful improvements in reducing mills,and particularly to that type of mills used for grinding, cutting feed,and the like, although, of course, it is obvious that there are manyother uses to which the mill may be put in practice.

The object of my present invention is to improve the revolving hammer bymaking the same preferably of commercially rolled metal in the form of aflat bar which may be bent from a single piece and secured in positionwithout the employment of fastening devices for holding or securing thefront and rear sections of the hammer together so that they will move inunison. By making a reversible hammer of the character described insubstantially a T form, I provide two active reducing edges at the frontand rear and when either of these edges is worn, the blade constitutingthe head of the hammer, or one portion of the head of the hammer, may bebent outwardly to compensate for wear. When a blade is worn to such anextent after repeated bendings, the hammer may be reversed and thebending operation again resorted to in adjusting the active reducingedge outwardly to take up wear.

Another object of my invention is to make a hammer of the characterdescribed more flexible by separating the shank portions thereof. and ifdesiredthinning the metal of said shank portions. whereby a yieldingresilient connection is produced between the hinge eye of thehamme'r'and the head portions thereof which permits the head portions tomore readily yield rearwardly in the event that they strike anobstruction such as a piece of metal accidentally fed into the machine.

In the drawings, 1 indicates the casing or housing, and 2 the hopper forfeeding material thereinto. 3 is a shaft carrying disks 4 between whichare pivotally mountedthe hammers 5 on bolts orrods 6 arranged in thedisks. 7 is a so called breaker plate and 8 the cage or screen havingopenings through which the reduced material passes from the machine.

My improved form 'of. T-shaped hammer is shown in Figure 3, in which9.indicates an eye portion preferably centrally located with respect toa length of commercially rolled flat bar of iron or steel. 10 designatesthe shank portions of the hammer which, as shown in Figure 3, areseparated or spaced apart throughout their length, an opening oropenings 11 being formed therein for the purpose of lightening thehammer and making these shank portions more flexible and yielding. 12are the head portions bent in opposite directions from the shankportions 10. l/Vhile these head portions may be straight, I prefer thatin their original form they shall be slightly curved on a lineconcentric to the innerface of the cage.

If it is desired to stiffen the shank portions so as to make them lessflexible or yielding, the outer ends thereof may be brought together sothat they will contact with and reinforce each other as shown in Figure4. In this Figure 4 the lightening openings in the shank portions havebeen omitted, the shank portions being shown as being solid.

In Figure 5 I have shown one of the head portions 12 as being concentricto the cage indicated by the dot and dash line 8*, While the other ofsaid head portions 12 has been bent outwardly so as to bring its activere ducing or" cutting edge close to the line 8 indicating the curvatureof the cage. As the edge of this hammer portion 12 'is worn away it maybe repeatedly bent outwardly, thus increasing its angular relation toits shank as shown in Figure- 6. During these bending operations of the,worn hammer head to compensate for wear, the angular position ofthe'rear head portion 12 need not be disturbed, as it has space to movetoward theline 8 when centrifugal force asserts itself and whichunbalancing of the hammer is taken advantage of, as'shown in Figure 7wherein the hammer has been reversed and its unworn head portion 12 isnow presented forwardly while its worn portion 12 is located at therear. In thisreversed position, the longer head portion l2 will travelin a path relatively close to the line 8 As this head portion 12 becomesworn, it may be bent outwardly as heretofore described. with res ect tothe head portion .12". this outward bending increasing the angularrelation between the worn head portion and its shank member as indicatedby dot ed lines 2 in Figure 7.

\VhatI claim is: V

1. A hammer for mills ofthe character de-' scribed comprising a flat barbent to form a shank with an eye at the inner end thereof and bent alonga line parallel to the eye portion to form a head portion extending inthe direction of rotation of the hammer.

2. A hammer for mills of the character described comprising a flat barbent to form a pivot eve by which the hammer may be mounted in position.the end of said eye being integral with shank portions and the outerends of said shank portions being bent forwardly and rearwardlyrespectively to form a reversible head portion 3. A hammer for mills ofthe character described consisting of 'a bar comprising flexible shanks,an eye atone end of said shanks'forpivotally mounting the hammer, andrigid head portions extending in opposite directions from the other endof'said shanks.

4:. A reversible hammer for machines of the class described including amalleable bar doubled on itself to form a laminated hammer shank, oneend of said bar extending diagonally away from the hammer axis to form ahammer head and the other end of said bar extending diagonally inwardlyfrom said head forming endto form a potential hammer head.

5. A-hammer for machines of the character described formed of flexiblematerial and provided witha mounting eye at one end said hammercomprising bars extending to form a reversible and adjustable reducinghead near the opposite end of the hammer in opposite directions at rightangles to the direction of the axis of said eye.

6. A hammer for mills of the character described comprising shankportions spaced from each other, joined at one end to form a pivot eye,and each provided at its other end with a head portion, said headportions extending in opposite directions, the spacing of said shankportions from each other and the direction of extension of saidheadportions being in a plane normal to the axis of the pivot eye.

7. 'A hammer for a beater mill comprising a single strip of metal bentat or near its central portion and transversely thereof forming amounting eyev at said bend and also shank portions and head portionsextending forwardly and rearwardly of said shank portions.

In testimony whereof I hereunto affix my signature this 30th day ofJune, l920.

FREDERICK R. CORNWALL.

